Dear Thomas,
Thank you for your nice review, we are happy you had a good time in Amsterdam.
Our reception works from 9AM to 9PM, during check in we always point out if you leave early to let us know the night before, so we can proceed your check out then. However our staff is always present in the hostel, there is just a note with a number and a phone to ring us in case of emergencies. Perhaps you overlooked this.
Love, Cocomama